var myName = "simon";
var myName2 = 'simon';
var myName3 = "ouyang";
var myIntr = "hello, \n    my name is " + myName + "\n";
var myIntr2 = "hello," + "\n" + "    my name is " + myName + "\n";
console.log(myIntr);
console.log(myIntr2);
var aa = "100";
var bb = "200";
console.log(aa + bb);
console.log((+aa) + (+bb));
